The -ultimate- SCSI accessory

[Bunsen]

Q: What can mount an IDE disk on a SCSI Mac, is Apple branded, and you probably have one in your scrap pile?

A: A dead Powerbook.

Bear with me.

Take one spare Powerbook, say a 1400. Maybe it has a cracked screen, or a broken trace around the video circuits. Maybe the case is irretrievably cracked and scuffed. Maybe it powers up, but for some reason refuses to boot. Maybe you've already stripped out all the connectors and cables and you're left with a bare motherboard and DC board.

Mount an IDE hard drive in it. If you can get hold of or make a reverse 2.5" to 3.5" adapter, like the one in the Centris Mini project, it can be a full size desktop drive. If you prefer small and quiet, you can use a 2.5" CF adapter.

Hook it up to your classic Mac with a SCSI Dock cable and power it up. Power up your classic.

Viola - SCSI to IDE [] ]'>

Now, it's true that the 1400 is limited to 4GB drives in SCSI Disk Mode because of a firmware bug. Presumably this bug exists in other 'books like the 5300 and 2300. Can anyone tell me if it also exists in the Wallstreets?

The last laptop with SCSI is the Lombard. It requires a working OS 9 partition on the drive to enter target disk mode, as it uses the "New World" software ROM file, rather than an actual ROM ROM.

Now, some might see this as a flaw...

}

Stay tuned for Part II

 

[tmtomh]

Cool! Hurry up with Part II...

 

[Quadraman]

Would this work with a PB 150? I have two with dead screens that otherwise work fine.

 

[benjgvps]

I have this 150 I am not using for too much since I got my 180c... Bunsen, you are the smartest man in the world!

 

[Bunsen]

Would this work with a PB 150?

Give it a shot and let us know! Use a small capacity IDE drive to be on the safe side - I don't know what the SCSI Disk Mode limit would be on those. IIRC you should be able to format the disk from the host Mac, but I could be wrong.

 

[MacJunky]

I don't think the 150 can support SCSI Disc Mode.. It says nothing in the documentation I have and according to a few sites as well.

http://lowendmac.com/tf/2k1129.html

http://docs.info.apple.com/article.html?artnum=16918-en

I would address one of your questions in the original post and test with my PowerBook G3 Series Rev 2 *if* I had the proper SCSI cable and *if* I had a decent sized HDD that had not failed like my PDQ's old 40GB samsung.

*Edit

Nevermind, an answer to the G3 PB topic in found at a developer.apple.com link here:

http://68kmla.org/forums/viewtopic.php?t=4388

 

[Bunsen]

Oh SWEET. I have two or three semi borked Wallstreets around here.

There is a problem with / SCSI disk mode / prior to the PowerBook G3 / The affected machines include the PowerBook Duo 2300c / 5300 / 190 / 1400 / 3400 / 2400

And there's your list of donor machines for ]'>

(sorry guys, no 150s [xx(] ]'> )

And here's your >4GB workaround:

partitioning a larger drive: a
So you can have a larger drive in there. You put aside the first 4GB to boot your Classic, and the rest to boot the laptop when you want. You can even have a shared partition, as long as it's in the first 4GB.

 

[Bunsen]

Part II

Network the Classic and the laptop over Ethernet or Appletalk. Have a small OS booting the laptop, and collect the appropriate software, on both sides, to bridge the laptop's plethora of devices to the classic (PCMCIA, USB, WiFI, DVD-ROM, &c) Use remote desktop software to control the Powerbook from the classic.

NB if you're using a really old Mac, with 1.5MB-5MB/s SCSI, and you've already managed to give it Ethernet, a network-mounted disk might actually be faster. You'd still need an internal boot drive, but that could well be a Disk Tools floppy.

Part IIa

Insert a shim to redirect network calls over the SCSI port, on both machines. In other words, have them both think they are using SCSI-Ethernet adapters, only they're not - they're connected direct to each other via SCSI. Then your classic doesn't even need Ethernet hardware - it can use whatever the Powerbook can serve up.

Part III (only for mad scientists)

Replace the ROM / ROM file with a new improved one that bridges onboard devices over SCSI in firmware. All the hardware is present: nothing needs to be built, it just needs reprogramming (and maybe a larger ROM chip) While you're in there, fix the >4GB bug

Either way, it would take a real DriverGuru *AHEM* to pull it off [] ]'>

 

[Bunsen]

I wonder if III could be achieved by Forth programming in Open Firmware?

 

[benjgvps]

Darn, I was hoping for a use for my 150 other than a serial terminal for my server.

I do think I could use the localtalk cable and make it a server with small apps to transfer or as an IRC machine if the cable can reach a comfortable area in my room, with my 180c running ethernet bridge.

 

[Bunsen]

(thread necromancy)

It occurs to me that with an IDE-CF and 2x PCMCIA-CF adapters, you could have three silent drives attached

 

[Trash80toHP_Mini]

Nice hack, B, I like! I'm glad you dredged this thread up, it died out almost a year before I got back from being AWOL.